Does your dog try to bury their waste with their Nose? (Litterbox)

This last week, my boy has decided that hes big enough now to bury his own waist with his nose. he shovels pellets on top of it just like the cat has shown him.
I'm disabled, and we have a lab puppy (service dog prospect, he will be doing retrieval and other tasks. I already have a trained service dog, but she's too small to do any retrieval). He has started doing this particularly funny thing. Our cat has gone to his litter box and covered his waste since he came home at 8 weeks. We have a litter box for the Lab, a tray of wood pellet bedding for horses that works great, so we don't need to worry too badly if I'm stuck in bed or miss a sign he needs to go out. My husband still gives him two walks a day, and he goes consistently in the tray or on the pad unless something upsets his tummy.
I'm flabbergasted at this new behavior as he does it right after he goes, but he uses his nose as a shovel for the pellets to cover his waste. Is this common for dogs who use a litter tray? Is my boy just an oddball? Ok, is he more of an oddball than normal?

Listen, I love Gary, hes a very good dog, not worried about his health or well-being, just very confused about where he got this idea. The Cat? His Soul? The single brain cell? Hes only 5 months old. Hes still got baby brain.